GNGTS 2018 - 37° Convegno Nazionale

670 GNGTS 2018 S essione 3.2 4. Post-dynamic step : ERT time-lapse measurements of the post-dynamic pressure dissipations. The most important result obtained was reached in the Dynamic step (Fig.2). The initial water level was at 8.7 cm below ground surface. After the first hit, perturbations of apparent resistivity (ρ app ) were observed up to the seventh hammer hits. The produced variations of ρ app Fig. 2 - ERT time-lapse measurements from step 2 to step 4. Left panels: ρ app resistivity variations for the two nodes highlighted with black circles in the right panels. Right panels: ρ app variations during the seismic input (upper) and post-seismic input (lower) across the sandbox, normalized with respect to the initial pseudosection. Fig. 3 - The self-potential (sp) collected data. The left upper panel represents the sp detrended data collected before the dynamic step and (left lower panel) the initial resistivity model related. On the other hand, the right upper panel represents the sp detrended data collected after the dynamic step and (right lower panel) the final resistivity model related.